Corpus ID: 236088188

The space of non-extendable quasimorphisms

  title={The space of non-extendable quasimorphisms},
  author={Morimichi Kawasaki and Mitsuaki Kimura and Shuhei Maruyama and Takahiro Matsushita and Masato Mimura},
In the present paper, for a pair (G,N) of a group G and its normal subgroup N , we consider the space of quasimorphisms and quasi-cocycles on N non-extendable to G. To treat this space, we establish the five-term exact sequence of cohomology relative to the bounded subcomplex. As its application, we study the spaces associated with the commutator subgroup of a Gromov hyperbolic group, the kernel of the (volume) flux homomorphism, and the IA-automorphism group of a free group. Furthermore, we… Expand

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